To go back to GWBN Homepage, click here
To go back to the Teamforce Homepage, click here

Vocabulary

---

inorganic- has not risen from materials that were once a living thing

crystal- has flat sides, called faces, that meet at sharp edges or corners

element- a substance composed of a single kind of atom

compound- two or more compounds are chemically merged so that the elements lose their once distinct properties

Mohs hardness scale- a scale, created by Fredrick Mohs, that ranks minerals by hardness on a scale of ten

streak- the color of a mineral's powder

cleavage- a mineral's ability to split against flat surfaces

fracture- the way a mineral looks when it splits apart in an unusual way

fluorescence- the mineral's ability to glow under ultra- violet light, or black light

Chapter Outline

---

T=

Properties of Minerals

• 3,000 known minerals
  • only 100 are common
  • twenty minerals form Earth's crust
    • minerals called "rock forming minerals"
  • Mineral=

    • naturally occurring

      • not made by people

      • inorganic

      • not arisen from once- living thing

    • solid

      • keeps shape, particles packed tightly

    • crystal structure

      • crystals grown in repeating pattern
    • definite chemical composition
      • has certain elements + definite proportions
      • almost all minerals are compounds
      • some elements occur pure form
        • copper
        • gold
        • silver

• Identifying Minerals

  • Each mineral has it's own specific properties that can be used to identify it.

    • Hardness

      • Mohs hardness scale
        • scale of ten, ten= hardest
        • mineral scratch any softer mineral

    • Color

      • used only with certain minerals

    • Streak

      • color of the powder
      • streak color= different from outside color

    • Luster

      • how a mineral reflects light
      • terms= waxy, earthy, pearly Density

*
** mass divided by volume= density

• Crystal Systems

  • crystal systems= crystals classified into shape
    • systems= cubic, hexagonal, tetragonal, orthorhombic, monoclinic, triclinic

• Cleavage

  • a minerals ability to split along flat surfaces= cleavage
    • minerals cleavage= how atoms on crystals are arranged
  • fracture= how a mineral looks when breaks apart irregularly

• Special Properties

  • minerals that glow in ultraviolet light (black light)= fluorescence
  • some minerals= magnetized
  • some minerals radioactive
  • some minerals react chemically towards acid